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 for <linuxppc-dev@lists.ozlabs.org>; Tue, 31 May 2016 09:29:52 +1000 (AEST)
Message-ID: <1464650992.16938.8.camel@ellerman.id.au>
Subject: Re: [PATCH 3/3] powerpc: Avoid load hit store when using
 find_linux_pte_or_hugepte()
From: Michael Ellerman <mpe@ellerman.id.au>
To: Anton Blanchard <anton@ozlabs.org>, benh@kernel.crashing.org,
 paulus@samba.org, aneesh.kumar@linux.vnet.ibm.com,
 acsawdey@linux.vnet.ibm.com
Cc: linuxppc-dev@lists.ozlabs.org
Date: Tue, 31 May 2016 09:29:52 +1000
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 <1464523432-12605-3-git-send-email-anton@ozlabs.org>
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On Sun, 2016-05-29 at 22:03 +1000, Anton Blanchard wrote:

> From: Anton Blanchard <anton@samba.org>
> 
> In many cases we disable interrupts right before calling
> find_linux_pte_or_hugepte().
> 
> find_linux_pte_or_hugepte() first checks interrupts are disabled
> before calling __find_linux_pte_or_hugepte():
> 
>         if (!arch_irqs_disabled()) {
>                 pr_info("%s called with irq enabled\n", __func__);
>                 dump_stack();
>         }

Should that be a VM_WARN_ON()?

cheers